Console communications are used in server systems to send and receive status, control and configuration information. Console communications are typically transmitted and received via a single LAN interface (i.e., a LAN that combines console and payload communications), or via a cable to an RS-232 port on a server.
When there is no console LAN, each server typically includes an RS-232 port for console communications. When a large number of servers are to be controlled, a complex, hard-to-manage wiring bundle to each individual server's RS-232 port must be implemented. Using an RS-232 port for console communications is sufficient for a standalone server, but when the server is integrated with many others in a common chassis, a separate cable for each server is difficult to maintain and configure. If any consolidation is to be done, it is typically implemented by a separate device outside of the chassis. Consequently, most customers route all of the cables a short distance to a special switch, such as those made by Raritan and Lantronics. Though this simplifies the cable bundle by giving a single port of access to the congregation of servers, it adds cost to the system in terms of money and space.
If a single LAN interface is used, there is a security hole in that LAN console control information commingles with payload information on a single customer payload LAN. This commingling of signals on a single LAN allows for unauthorized snooping, and the potential for unauthorized communications to the console devices. For a single LAN interface, a security driven software layer can used (at additional cost), but there is a possibility that the security layer could be compromised.
It would be desirable for a server system to provide a more convenient and secure console communication system.